After you create and deploy an application in Enterprise Distributed Application Service (EDAS), you may need to update the application. If an updated application does not run as normal, you can roll back the application to its earlier version. This topic describes how to update and roll back an application.
Update an application
The following table lists the update policies and methods that you can use to update an application in different scenarios.
Update policy | Scenario | Update method | References |
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At-a-time release | If an application has a small number of instances or has a simple service architecture, you can directly update the application after you develop and test the application. You can directly deploy a new version of the application. |
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Phased release | If an application has a large number of instances or has a complex service architecture, you can release the application in multiple phases. The application is updated only on a few instances in each phase. The phased release is complete when the application is updated on all the instances. If an error occurs during the phased release, you can terminate the process and roll back the application. You can release the application again after the error is fixed. |
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Canary release | A new application version needs to be verified on a small number of instances. If the verification is successful, you can update the application on all instances. | Console | Release an application in canary mode in an ECS cluster in the EDAS console |
Roll back an application
If an error occurs when or after you update an application, you can roll back the application to its earlier version. After you fix the error, you can update the application again.
- If an error occurs when you update the application, stop the update process and roll back the application.
- If an error occurs after you update the application, roll back the application to its earlier version.
For more information, see Use the EDAS console to roll back applications in ECS clusters.